Surf Load (Part II)

In the sea, you will find it funny that large volumes bodies, is terms as hydrodynamics compact structures, how the shape of the body influence the wave field is by: diffraction and reflection. For reflection, it is easy to explained but for diffraction will be need more heavy mental lifting. Like me, you might ask why do they label big volumes bodies as compact because you reason like me hey man compact camera= small camera. No answer man. Just remember diffraction is the bending of wave when hit small obstacles.

So the forces on this bodies are to be calculated by using the diffraction theory.

How about the slender, hydrodynamic transparent structures that have no significant influence on the wave field. We can calculated the forces in a straight foward manner with Morison's equation. So we use morison equation when the D(member dia.)/L(wave length) < 0.2. This idea may be very abstract if you look into it for the first time.

Let talk about Morrion's equation in more detailed, you see the morison's equation expresses the wave force as teh sum of

1. an inertia force proportional to the particle acceleration
2. a non linear drag force proportional to the square of the particle velocity.